Decoupled spacer and plate and method of installing the same

ABSTRACT

Intervertebral spacer assemblies, systems, and methods thereof. A method of insertion includes inserting an intervertebral spacer and plate together using an insertion tool and, upon removal of the insertion tool, the intervertebral spacer and plate are no longer considered connected/coupled and act as separate components.

REFERENCE TO RELATED APPLICATIONS

The present application is a divisional of U.S. application Ser. No.15/867,073, filed Jan. 10, 2018, which is a continuation-in-part of U.S.application Ser. No. 15/661,027, which is a continuation-in-partapplication of U.S. application Ser. No. 15/479,438, filed Apr. 5, 2017,which are hereby incorporated by reference in their entireties for allpurposes.

BACKGROUND Field of the Invention

The present invention relates to bone fixation, and more specifically,to a method of installing an intervertebral spacer and plate.

Description of the Related Art

Various types of spacers can be used in spinal fusion procedures. Astandalone spacer is one in which a spacer is attached to a plate. Theplate is configured to receive one or more screws that secure thestandalone spacer to one or more adjacent vertebrae. The combinedspacer/plate structure is typically rigid, thereby reducing theflexibility of the patient at the implant site.

There exists a need for intervertebral spacer and plate assemblies thatare inserted as a unit with an insertion tool, but are decoupled fromeach other when the insertion tool is removed. Further, methods ofinserting the assemblies are also needed.

SUMMARY

To meet this and other needs, implants, systems and methods are providedto permit the insertion of a plate and spacer together or separately. Ifthe plate and spacer are used together, a holder or group of holdinginstruments can be used to hold both the plate and spacer togetherduring the insertion process. For example, the attachment of the plate,spacer and holder may be provided with a threaded rod without violatingthe graft space within the spacer. Additionally, embodiments may includea threaded rod and holder whose material and geometry lend to the rodcurving within the holder, permitting the angular attachment of thesecomponents. Other embodiments of the plate, spacer, and instruments aredescribed herein.

According to one embodiment, a method of installing an intervertebralspacer and plate assembly may include coupling an intervertebral spacerand plate to an insertion tool; delivering the coupled spacer and plateto a surgical site via the insertion tool, wherein the spacer and/orplate are received in an intervertebral disc space; inserting one ormore bone screws into the plate to secure the plate to one or moreadjacent vertebrae; and removing the insertion tool, such that thespacer is decoupled from the plate at the surgical site.

BRIEF DESCRIPTION OF THE DRAWINGS

Other aspects, features, and advantages of the present invention willbecome more fully apparent from the following detailed description, theappended claims, and the accompanying drawings in which like referencenumerals identify similar or identical elements.

FIG. 1 is a perspective view of a spacer and plate assembly according toa first exemplary embodiment;

FIG. 2 is a perspective view of the spacer shown in FIG. 1;

FIGS. 3-6 show a top plan view, posterior elevational view, left lateralside elevational view, and right lateral side elevational view,respectively of the spacer shown in FIG. 2;

FIG. 7 is a perspective view of the plate shown in FIG. 1;

FIGS. 8-11 show a posterior elevational view, top plan view, leftlateral side elevational view, and right lateral side elevational view,respectively, of the plate shown in FIG. 7;

FIGS. 12-14 show a top plan view, posterior elevational view, and rightlateral side elevational view, respectively, of the assembly shown inFIG. 1;

FIG. 15 is a left lateral side elevational view of the spacer of FIG. 1;

FIG. 16 is a perspective view of the assembly components shown in FIG. 1and an insertion tool for inserting the assembly;

FIG. 17 is a perspective view showing the plate of FIG. 7 having beeninserted onto the insertion tool;

FIG. 18 is a perspective view showing the spacer and plate assembly ofFIG. 1 having been inserted onto the insertion tool;

FIG. 19 is a top plan view, in section, of the plate and spacer of theassembly shown in FIG. 1 having been inserted onto the insertion tool;

FIG. 20 is a top plan view of a spacer and plate assembly according to asecond exemplary embodiment;

FIGS. 21-24 are a posterior elevational view, left lateral sideelevational view, exploded posterior perspective view, and explodedanterior perspective view, respectively, of the assembly shown in FIG.20;

FIG. 25 is a top plan view, in section, of the plate of FIG. 20 and aninsertion tool for inserting the plate;

FIG. 26 is a perspective view of the plate and insertion tool of FIG.25;

FIG. 27 is a top plan view, in section, of the assembly of FIG. 20 andthe insertion tool for inserting the assembly;

FIG. 28 is a perspective view of the assembly and insertion tool of FIG.27;

FIG. 29 is a top plan view, in section, of a spacer block and the spacerand insertion tool of FIG. 27;

FIG. 30 is a perspective view of the spacer block, spacer, and insertiontool of FIG. 29;

FIG. 31 is a top plan view of a spacer and plate assembly according to athird exemplary embodiment;

FIGS. 32-35 are a posterior elevational view, left lateral sideelevational view, exploded anterior perspective view, and explodedposterior perspective view, respectively, of the assembly shown in FIG.31;

FIG. 36 is a top plan view, in section, of the plate of FIG. 31 and aninsertion tool for inserting the assembly of FIG. 31;

FIG. 37 is a perspective view of the plate and insertion tool of FIG.36;

FIG. 38 is a top plan view, in section, of the assembly of FIG. 31 andthe insertion tool for inserting the assembly;

FIG. 39 is a perspective view of the assembly and insertion tool of FIG.38;

FIG. 40 is a top plan view, in section, of a spacer block and the spacerand insertion tool of FIG. 38;

FIG. 41 is a perspective view of the spacer block, spacer, and insertiontool of FIG. 40;

FIG. 41A is an anterior perspective view of an alternative plate for usewith the spacer shown in FIG. 20;

FIGS. 41B-41D are a left perspective view, left side elevational view,anterior side elevational view, respectively of the plate shown in FIG.41A;

FIG. 42 is a top plan view of a spacer and plate assembly according to afourth exemplary embodiment;

FIGS. 43-46 are a posterior elevational view, left lateral sideelevational view, exploded anterior perspective view, and explodedposterior perspective view of the assembly shown in FIG. 42;

FIG. 47 is a top plan view, in section, of the plate of FIG. 42 and aninsertion tool for inserting the assembly of FIG. 42;

FIG. 48 is a perspective view of the plate and insertion tool of FIG.47;

FIG. 49 is a top plan view, in section, of the assembly of FIG. 42 andthe insertion tool for inserting the assembly;

FIG. 50 is a perspective view of the assembly and insertion tool of FIG.49;

FIG. 51 is a top plan view, in section, of a spacer block and the spacerand insertion tool of FIG. 49;

FIG. 52 is a perspective view of the spacer block, spacer, and insertiontool of FIG. 51;

FIG. 53 is a top plan view of a spacer and plate assembly according to afifth exemplary embodiment;

FIGS. 54-57 are a posterior elevational view, left lateral sideelevational view, exploded anterior perspective view, and explodedposterior perspective view, respectively, of the assembly shown in FIG.53;

FIG. 58 is a top plan view, in section, of the assembly of FIG. 53attached to an insertion tool for inserting the assembly of FIG. 53;

FIG. 59 is a perspective view of the assembly and insertion tool of FIG.58;

FIG. 60 is a top plan view, in section, of the plate of FIG. 53 and theinsertion tool for inserting the plate;

FIG. 61 is a perspective view of the plate and insertion tool of FIG.60;

FIG. 62 is a top plan view, in section, of a spacer block and the spacerand insertion tool of FIG. 59;

FIG. 63 is a perspective view of the spacer block, spacer, and insertiontool of FIG. 62;

FIG. 64 is a top plan view of a spacer and plate assembly according to asixth exemplary embodiment;

FIGS. 65-67 re a left lateral side elevational view, posteriorelevational view, and exploded anterior perspective view, respectively,of the assembly of FIG. 64;

FIG. 68 is a perspective view of a spacer and plate assembly accordingto a seventh exemplary embodiment;

FIG. 69 is a perspective view of a spacer used with the assembly shownin FIG. 68;

FIG. 70 is a perspective view of a plate used with the assembly shown inFIG. 68;

FIGS. 71-74 are a top plan view, anterior elevational view, right sideelevational view, and left side elevational view, respectively, of thespacer shown in FIG. 69;

FIGS. 75-78 re an anterior elevational view, top plan view, right sideelevational view, and left side elevational view, respectively, of theplate shown in FIG. 70;

FIGS. 79-82 re a top plan view, anterior elevational view, right sideelevational view, and left side elevational view, respectively, of theassembly shown in FIG. 68;

FIG. 83 is a perspective view of a spacer and plate assembly accordingto an eighth exemplary embodiment;

FIG. 84 is a perspective view of a spacer used with the assembly shownin FIG. 83;

FIG. 85 is a perspective view of a plate used with the assembly shown inFIG. 83;

FIGS. 86-89 are a top plan view, anterior elevational view, right sideelevational view, and left side elevational view, respectively, of thespacer shown in FIG. 84;

FIGS. 90-93 is an anterior elevational view, a posterior elevationalview, right side elevational view, and a top plan view of the plateshown in FIG. 85;

FIGS. 94-97 is a top plan view, anterior elevational view, right sideelevational view, and left side elevational view of the assembly shownin FIG. 83;

FIG. 98 is a side elevational view, in section, of the assembly shown inFIG. 94, taken along lines 98-98 of FIG. 94;

FIG. 99 is a perspective view of a spacer and plate assembly accordingto a ninth exemplary embodiment;

FIG. 100 is a perspective view of a spacer used with the assembly shownin FIG. 99;

FIG. 101 is a perspective view of a plate used with the assembly shownin FIG. 99;

FIGS. 102-105 is a perspective view, top plan view, anterior elevationalview, and posterior elevational view of the spacer shown in FIG. 100;

FIGS. 106-109 is top plan view, perspective view, anterior elevationalview, and posterior elevational view of the plate shown in FIG. 101;

FIGS. 110-113 is a top plan view, anterior elevational view, right sideelevational view, and left side elevational view of the assembly shownin FIG. 99;

FIG. 114 is an anterior elevational view of a spacer and plate assemblyaccording to a tenth exemplary embodiment;

FIGS. 115-116 is a top plan view and right side elevational view of theassembly shown in FIG. 114;

FIG. 117 is a top plan view of a spacer and plate assembly according toan eleventh exemplary embodiment;

FIG. 118 is a top plan view of a spacer and plate assembly according toa twelfth exemplary embodiment;

FIG. 119 is a top plan view of a spacer and plate assembly according toa thirteenth exemplary embodiment;

FIG. 120 is a top plan view of a spacer and plate assembly according toa fourteenth exemplary embodiment;

FIG. 121 is a top plan view of a spacer and plate assembly according toa fifteenth exemplary embodiment;

FIG. 122 is a top plan view of a spacer and plate assembly according toa sixteenth exemplary embodiment;

FIG. 123 is posterior side elevation view of a spacer according to aseventeenth exemplary embodiment;

FIG. 124 is an anterior side elevation view of the spacer shown in FIG.123;

FIG. 125 is a top plan view of the spacer shown in FIG. 123, with aplate and insertion device;

FIG. 126 is a top plan view of a spacer and plate assembly according toan eighteenth exemplary embodiment;

FIG. 127 is a posterior side elevation view of the assembly shown inFIG. 126;

FIG. 128 is a top plan view of a spacer and plate assembly according toa nineteenth exemplary embodiment;

FIG. 129 is a posterior side elevation view of the plate shown in FIG.128;

FIG. 130 is a posterior side elevation view of the spacer of FIG. 128;

FIG. 131 is a top perspective view of a spacer and plate assemblyaccording to a nineteenth embodiment;

FIGS. 132-134 is a top view, side view, and posterior view of theassembly shown in FIG. 131;

FIG. 135 is a posterior view of the spacer shown in FIG. 131;

FIG. 136 is a top perspective view of the assembly shown in FIG. 131attached to an insertion tool;

FIGS. 137-139 is a top view, side view, and bottom view of the assemblyshown in FIG. 131 attached to an insertion tool;

FIGS. 140A-140C illustrate the insertion tool being attached to thespacer and plate assembly in accordance with some embodiments;

FIG. 141 is a top perspective view of a spacer and plate assemblyaccording to a twentieth embodiment;

FIG. 142-145 is a top view, side view, bottom view, posterior view ofthe assembly shown in FIG. 141;

FIGS. 146A-146C illustrate the spacer and plate assembly with thegripping features of the plate in a neutral position in accordance withsome embodiments;

FIGS. 147A-147C illustrate the spacer and plate assembly with thegripping features of the plate in a compressed position in accordancewith some embodiments.

FIG. 148 is a top perspective view of a spacer and plate assemblyaccording to a twenty-first embodiment;

FIG. 149 is a posterior view of the assembly shown in FIG. 148;

FIG. 150 is a sectional view of the assembly shown in FIG. 149, takenalong lines 150-150 of FIG. 149;

FIG. 151 is a posterior view of the spacer shown in FIG. 148;

FIG. 152 is a posterior view of the plate shown in FIG. 148;

FIG. 153 is a perspective view of the spacer and plate assembly of FIG.148, attached to a holder;

FIG. 154 is a top plan view of the spacer and plate assembly and theholder of FIG. 153;

FIG. 155 is a side elevational view of the spacer and plate assembly andthe holder of FIG. 153;

FIG. 156 is a sectional view of the spacer and plate assembly and theholder of FIG. 155, taken along lines 156-156 of FIG. 155;

FIG. 157 is a perspective view of the spacer and plate assembly and theholder of FIG. 153, in a disassembled condition;

FIG. 158 is a perspective view of the spacer and plate assembly and theholder of FIG. 157, with the shaft inserted into the holder;

FIG. 159 is a perspective view of the spacer and plate assembly and theholder of FIG. 158, with the plate attached to the holder; and

FIG. 160 is a perspective view of the spacer and plate assembly and theholder of FIG. 159, with the spacer attached to the holder.

DETAILED DESCRIPTION

In the drawings, like numerals indicate like elements throughout.Certain terminology is used herein for convenience only and is not to betaken as a limitation on the present invention. The terminology includesthe words specifically mentioned, derivatives thereof and words ofsimilar import. The embodiments illustrated below are not intended to beexhaustive or to limit the invention to the precise form disclosed.These embodiments are chosen and described to best explain the principleof the invention and its application and practical use and to enableothers skilled in the art to best utilize the invention.

In performing spinal fusion procedures, a spacer can be inserted into adisc space. In some embodiments, a standalone spacer can be attached toa plate. The plate can receive one or more bone anchors or screws toattach to the plate to one or more adjacent vertebrae. The plate andspacer are often rigidly connected and are not decoupled from oneanother.

The present application includes spacer and plate assemblies that can becoupled via an insertion instrument upon delivery to a surgical site. Insome embodiments, a surgical site can be at or near a disc space, as oneskilled in the art will appreciate. The insertion instrumentadvantageously provides a single tool for delivering both the spacer andplate if desired. Once the spacer and plate are implanted at thesurgical site, the insertion instrument can be removed. With theinsertion instrument removed, the spacer and plate are considereddecoupled from one another. By providing a spacer and plate that areindependent and decoupled from one another, a surgeon advantageously hasthe option to implant both a plate and a spacer, a spacer by itself, ora plate by itself if desired.

The present disclosure provides embodiments of intervertebral spacersand plates that can be used to space and fixedly secure two adjacentvertebrae. According to one embodiment, shown in FIGS. 1-19, anintervertebral spacer and plate assembly 100 (“assembly 100”) isprovided. In an exemplary embodiment, assembly 100 can be used forcervical repair, although those skilled in the art will recognize thatassembly 100 can be sized for thoracic or lumbar repair as well.

Assembly 100 is formed from two separate components, an intervertebralspacer 102 and a plate 104. In some embodiments, spacer 102 and plate104 are not directly connected to each other, but are instead eachseparately coupled to an insertion tool 106, shown in FIGS. 16-19.

Referring to FIGS. 1-6, spacer 102 includes a body 108 having a superiorsurface 110 and an opposing inferior surface 112. Each of superiorsurface 110 and inferior surface 112 can have a plurality of protrusionsor fixation elements 114 extending outwardly therefrom. While fixationelements 114 are shown as being generally pyramidal in shape, thoseskilled in the art will recognize that fixation elements 114 can beother shapes, such as ribbed, or other suitable shapes. Fixationelements 114 are used to bite into a grip each of adjacent vertebrae(not shown) between which spacer 102 is inserted.

As shown in FIG. 2, body 102 can have a generally U-shape, withgenerally parallel lateral sides 116, 118, connected to each other by ananterior portion 120. Lateral side 116 includes a convex arcuateposterior face 117 while lateral side 118 includes a convex arcuateposterior face 119. The space between lateral sides 116, 118 canoptionally be filled with graft material. The advantage of a U-shapedbody is that if a surgeon decides to use the spacer 102 on its own, itcan be easily backfilled through the opening of the “U”. Referring toFIGS. 2-4, superior surface 110 along lateral side 118 includes a cutout111 that slopes inferiorly in an anterior-to posterior direction.Similarly, inferior surface 112 along lateral side 116 includes a cutout113 that slopes superiorly in an anterior-to posterior direction.Cutouts 111, 113 allow for securing screws (not shown) to be insertedthrough plate 104, along cutouts 111, 113, respectively, and intoadjacent vertebrae (not shown) without engaging spacer 102.

Lateral side 116 includes a tubular protrusion 122 extending in ananterior-posterior direction. Protrusion 122 has an internally threadedpassage 124 that is sized to accept a portion of insertion tool 106 aswill be explained in detail below. Passage 124 can have a closedanterior end 125.

Lateral side 118 includes an open slot 126 that extends in ananterior-posterior direction. An anterior end 128 of slot 126 extendsmedially inward and is sized to accept a portion of insertion tool 106as will be explained in detail below.

Referring now to FIGS. 1 and 7-11, plate 104 includes a body 130 havinga superior surface 132 and an opposing inferior surface 134. In someembodiments, the plate 104 is sized and configured to be received withina disc space, while in other embodiments, at least a portion of theplate 104 is sized and configured to be received outside of a discspace. Each of superior surface 132 and inferior surface 134 can have aplurality of stabilizer elements 136 extending outwardly therefrom. Insome embodiments, the stabilizer elements 136 can be for torsionalstabilization. In an exemplary embodiment, one stabilizer element 136 islocated along a central anterior-to-posterior axis, and a secondstabilizer element 136 is located proximate to a lateral side of body130. While stabilizer elements 136 are shown as being generally ribbedin shape, those skilled in the art will recognize that stabilizerelements 136 can be other shapes, such as pyramidal, or other suitableshapes. Stabilizer elements 136 are used to bite into a grip each ofadjacent vertebrae (not shown) between which spacer 102 is inserted.

As shown in FIG. 9, body 130 can have a generally arcuate shape, withgenerally parallel lateral sides 138, 140. Each lateral side 138, 140includes an anterior-to-posterior slot 142, 144, respectively. Slot 142includes a superior surface 146 and a generally parallel inferiorsurface 148, while slot 144 includes a superior surface 150 and agenerally parallel inferior surface 152. As shown in FIG. 13, when plate104 is aligned with spacer 102 for insertion, slot 142 is aligned withthreaded passage 124 and slot 144 is aligned with open slot 126.

Body 130 includes a generally concave arcuate anterior face 156 thatmates with convex arcuate faces 117, 119 of spacer 102 when plate 104 islocated against spacer 102, as shown in FIG. 12. Body 130 also includesa generally convex posterior face 158 that extends generally parallel toanterior face 156.

Through-holes 160, 162 extend through body 130 in aposterior-to-anterior direction. Through-holes 160, 162 are sized toallow a bone or securing screw (not shown) to be inserted therethroughto secure plate 104 to each of a superior vertebra (not shown) and aninferior vertebra (not shown), between which spacer 102 is beinginserted. Through-hole 160 extends in a superior-to-inferior directionso that its screw engages and secures to the inferior vertebra, whilethrough-hole 162 extends in an inferior-to-superior direction so thatits screw engages and secures the superior vertebra.

A locking screw 164 is disposed between through-holes 160, 162. Lockingscrew 164 has a head 166 with diametrically opposed arcuate cutouts 168,170 that are sized to allow the securing screws discussed above to beinserted into through-holes 160, 162. During insertion of assembly 100,locking screw 164 is in a configuration relative to plate 104 as shownin FIG. 8. After the securing screws secure plate 104 to the superiorand inferior vertebra, locking screw 164 is rotated, for example, about90 degrees, so that head 166 extends over the securing screws,preventing the securing screws from inadvertently backing out.

FIGS. 1 and 12-15 show assembly 100. While plate 104 abuts spacer 102,plate 104 is not rigidly connected to spacer 102 in any way so thatspacer 102 and plate 104 remain separate, independent components. Duringinsertion via an insertion tool, the spacer 102 and plate 104 can bothbe coupled to the insertion tool. After insertion to a surgical site,the spacer 102 and plate 104 are decoupled from one another.

Referring now to FIGS. 16-19, insertion tool 106 is used to insertspacer 102 and plate 104. Insertion tool 106 includes a distal end 170having a first distal finger 172 and a second distal finger 174 thatextends generally parallel to first distal finger 174. A gap 176 betweenfingers 172, 174 forms a generally U-shaped cavity 176 that is sized toaccept plate 104 therein, as shown in FIG. 17. This gap advantageouslyprovides space for a surgeon to use a tool to insert one or more bonescrews or anchors into the plate. First distal finger 172 includes a rod178 having a threaded end 180 that threads into threaded passage 124 intubular protrusion 122 on spacer 102, as shown in FIG. 19. Rod 178 has aproximal end (not shown) that can be rotated by the surgeon tothreadingly secure threaded end 180 into threaded passage 124.

Second distal finger 174 includes a prong 182 that extends generallytoward first distal finger 172. Prong 182 is sized to fit into anteriorend 128 of slot 126 on spacer 102.

While a single insertion tool 106 is shown, those skilled in the artwill recognize that multiple insertion tools can be used. For example, afirst insertion tool having only first distal finger 172 can be used inconjunction with a second insertion tool having only second distalfinger 174.

According to one embodiment, a method of installing assembly 100, forexample, at the site of two adjacent vertebrae (not shown), may includeproviding spacer 102, plate 104, and insertion tool 106 as a kit, asshown in FIG. 16. Referring to FIG. 17, plate 104 is connected toinsertion tool 106 such that distal end 170 of insertion tool 106extends distally of plate 104 (shown in FIG. 19). Plate 104 is connectedto insertion tool 106 by attaching plate 104 to each of first finger 172and second finger 174. First finger 172 is inserted into slot 142, whilesecond finger 174 is inserted into second slot 144. Plate 104 is slidproximally onto each of first finger 172 and second finger 174, withplate 104 engaging each of first finger 172 and second finger 174 withan interference fit.

Next, as shown in FIGS. 18 and 19, spacer 102 is attached to distal end170 of insertion tool 106 by attaching spacer 102 to each of firstfinger 172 and second finger 174. Sequentially or simultaneously, firstfinger 172 is connected to spacer 102 by threading threaded end 180 thatthreads into threaded passage 124 in tubular protrusion 122 on spacer102 and inserting prong 182 on second finger 174 into slot 126 on spacer102 and sliding spacer 102 proximally until prong 182 engages anteriorend 128 of slot 126, thereby frictionally engaging second finger 174with spacer 102.

After assembly 100 is attached to insertion tool 106, spacer 102 isinserted between adjacent vertebrae. Gap 176 is sufficiently largebetween plate 104 and insertion tool 106 to allow securing devices, suchas, for example, screws (not shown) to be inserted through through-holes160, 162, and into inferior vertebra and superior vertebra,respectively, securing plate 104 to the vertebrae. After securing plate104 to the vertebrae, insertion tool 106 is removed, leaving spacer 102and plate 104, as separate components, in the patient's spinal column.While the plate 104 and spacer 102 are attached to the insertion tool106 upon delivery to a surgical site, once the insertion tool 106 isremoved, the plate 104 and spacer 102 can be viewed as decoupled orindependent from one another.

An alternative embodiment of an intervertebral spacer and plate assembly200 (“assembly 200”) is shown in FIGS. 20-28. In an exemplaryembodiment, assembly 200 can be used for lumbar repair, although thoseskilled in the art will recognize that assembly 200 can be sized forthoracic or cervical repair as well.

Assembly 200 is formed from two separate components, an intervertebralspacer 202 (“spacer 202”) and a plate 204 (“plate 204”). In someembodiments, spacer 202 and plate 204 are not connected to each other,but are instead each separately coupled to an insertion tool 206, asshown in FIGS. 25-28.

Referring to FIGS. 20 and 22-24, spacer 202 includes a body 208 having asuperior surface 210 and an opposing inferior surface 212. Each ofsuperior surface 210 and inferior surface 212 can have a plurality ofprotrusions or fixation elements 214 extending outwardly therefrom.While fixation elements 214 are shown as being generally pyramidal inshape, those skilled in the art will recognize that fixation elements214 can be other shapes, such as ribbed, or other suitable shapes.Fixation elements 214 are used to bite into a grip each of adjacentvertebrae (not shown) between which spacer 202 is inserted.

As shown in FIG. 20, body 202 can have a generally oblong shape, withgenerally arcuate lateral sides 216, 218, connected to each other by ananterior portion 220 and a posterior portion 222. Lateral side 216includes an indentation 217 while lateral side 218 includes a similarindentation 219. Indentations 217, 219 reduce the lateral length ofposterior portion 222 relative to the remaining lateral length of spacer202. A space 223 bounded by lateral sides 216, 218, anterior portion220, and posterior portion 222 can optionally be filled with graftmaterial.

Posterior portion 222 includes a first chamfered face 224 that extendsin an inferior direction posteriorly from superior surface 210 and asecond chamfered face 226 (shown in FIG. 23) that extends in a superiordirection posteriorly from inferior surface 212. Chamfered faces 224,226 allow for securing screws (not shown) to be inserted through plate204, along chamfered faces 224, 226, respectively, and into adjacentvertebrae (not shown) without engaging spacer 202.

Posterior portion 222 also includes a smooth, anteriorly directed hole228 proximate to lateral side 216. Hole 228 is sized to accept anon-threaded portion of insertion tool 206 as will be explained indetail below. Posterior portion 222 also includes a threaded, anteriorlydirected hole 229 proximate to lateral side 218. Hole 229 is sized toaccept a threaded portion of insertion tool 206 as will be explained indetail below.

Referring now to FIGS. 20-24, plate 204 includes a body 230 having asuperior surface 232 and an opposing inferior surface 234. Each ofsuperior surface 232 and inferior surface 234 can have a plurality ofstabilizer elements 236 extending outwardly therefrom. In someembodiments, the stabilizer elements 236 can be for torsionalstabilization. In an exemplary embodiment, stabilizer elements 236 arelocated along fingers 238, 240 that extend anteriorly from plate 204.While stabilizer elements 236 are shown as being generally ribbed inshape, those skilled in the art will recognize that stabilizer elements236 can be other shapes, such as pyramidal, or other suitable shapes.Stabilizer elements 236 are used to bite into a grip each of adjacentvertebrae (not shown) between which spacer 202 is inserted.

As shown in FIG. 20, body 230 can have a generally laterally elongateshape, with generally parallel lateral sides 242, 244. Fingers 238, 240extend from lateral sides 242, 244, respectively. Fingers 238, 240 aresized to fit into indentations 217, 219 respectively, while a spacebetween fingers 238, 340 is sized to allow posterior portion 222 ofspacer 202 to be inserted therein.

Referring to FIG. 21, through-holes 260, 262 extend through body 230 ina posterior-to-anterior direction. Through-holes 260, 262 are located onplate 204 to align with holes 228, 229 when plate 204 and spacer 202 arecoupled as shown in FIG. 20. Through-hole 260 can be smooth bored toallow for the passage of the non-threaded portion of insertion tool 206.Through-hole 262 can be smooth bored or threaded to allow for theinsertion of the threaded portion of insertion tool 206.

Additional through-holes 264, 266, 268 are provided in plate 204 and aresized to allow a securing screw (not shown) to be inserted therethroughto secure plate 204 to each of a superior vertebra (not shown) and aninferior vertebra (not shown), between which spacer 202 is beinginserted. Through-holes 264, 266 each extends in a superior-to-inferiordirection so that their respective screw each engages and secures to theinferior vertebra, while through-hole 268 extends in aninferior-to-superior direction so that its screw engages and secures thesuperior vertebra.

Referring to FIG. 21, locking screws 270, 272, 274 are each is disposedadjacent to a respective through-hole 264, 266, 268. Each locking screw270, 272, 274 has a head 276, 278, 280 with an arcuate cutout 283, 285,287, respectively, that is sized to allow the securing screws discussedabove to be inserted into through-holes 264, 266, 268. During insertionof assembly 200, locking screws 270, 272, 274 are in a configurationrelative to plate 204 as shown in FIG. 21. After the securing screwssecure plate 204 to the superior and inferior vertebra, locking screws270, 272, 274 are rotated, for example, about 90 degrees, so that heads276, 278, 280 each extends over its adjacent securing screws, preventingthe securing screws from inadvertently backing out.

FIGS. 20-24, 27, and 28 show assembly 200. While plate 204 is butted upagainst spacer 202 to form a coupled construct, plate 204 is notconnected to spacer 202 so that spacer 202 and plate 204 remainseparate, independent components that can be implanted together or ontheir own as part of a fusion procedure.

Referring now to FIGS. 25-28, insertion tool 206 is used to insertspacer 202 and plate 204. Insertion tool 206 includes a distal end 282having a first distal finger 284 and a second distal finger 286 thatextends generally parallel to first distal finger 282. First distalfinger 282 is a generally smooth bore rod that is sized to pass throughthrough-hole 260 in plate 204 and into hole 228 in spacer 202.

Second distal finger 286 includes a rod 288 having a threaded end 289that threads into threaded through-hole 262 in plate 204, as shown inFIG. 25, as well as into hole 229 in spacer, as shown in FIG. 27. Rod288 has a proximal end (not shown) that can be rotated by the surgeon tothreadingly secure threaded end 289 into hole 229.

While a single insertion tool 206 is shown, those skilled in the artwill recognize that multiple insertion tools can be used. For example, afirst insertion tool having only first distal finger 282 can be used inconjunction with a second insertion tool having only second distalfinger 286.

According to one embodiment, a method of installing assembly 200, forexample, at the site of two adjacent vertebrae (not shown), may includeproviding spacer 202, plate 204, and insertion tool 206 as a kit, asshown in FIG. 28.

As shown in FIGS. 23 and 24, plate 204 is releasably engaged with spacer202 in the absence of securing plate 204 to spacer 202 such that plate204 engages spacer 202 between first finger 238 and second finger 240,as shown in FIG. 20.

Next, insertion tool 206 is inserted through plate 204 and into spacer202. Such insertion is performed by inserting insertion tool 206 throughfirst through-hole 260 and second through-hole 262 and into holes 228,229 of spacer 202. This is accomplished by threading threaded finger 286of insertion tool 206 into plate 204 and into hole 229 in spacer 202, aswell as inserting unthreaded finger 282 of insertion tool 206 throughplate 204 and into hole 228 in spacer 202.

Next, spacer 202 is implanted between adjacent vertebrae. Insertion tool206 is removed such that spacer 202 is separate from plate 204. Next,plate 204 is connected to the vertebrae.

Optionally, as shown in FIGS. 25 and 26, insertion tool 206 can bereleasably secured to only plate 204. Then, plate 204 can be coupled tospacer 202, after which time insertion tool 206 is then releasablysecured to spacer 202.

A situation may arise wherein plate 204 is not required to secure spacer202 between adjacent vertebrae; the compression of vertebrae toward eachother is sufficient to maintain spacer 202 in place. In such asituation, plate 204 can be omitted. It is desired, however, toincorporate a substitute for plate 204 in order to provide desiredspacing between plate 202 and insertion tool 206.

To achieve this spacing, as shown in FIGS. 29 and 30, a spacer block 290is provided. Spacer block 290 has substantially the sameanterior-to-posterior width as plate 204, but without fingers 238, 240.Spacer block 290 includes a pair of unthreaded, smooth borethrough-holes 292, 294 that align with holes 228, 229 of spacer 202 sothat fingers 282, 286 of insertion tool 206 can be inserted therethroughand into hole 228, 229 of spacer 202 for insertion of spacer 202 betweenadjacent vertebrae (not shown).

An alternative embodiment of an intervertebral spacer and plate assembly300 (“assembly 300”) is shown in FIGS. 31-39. In an exemplaryembodiment, assembly 300 can be used for lumbar repair, although thoseskilled in the art will recognize that assembly 300 can be sized forthoracic or cervical repair as well.

Assembly 300 is formed from two separate components, an intervertebralspacer 302 (“spacer 302”) and a plate 304 (“plate 304”). In someembodiments, spacer 302 and plate 304 are not connected to each other,but are instead each separately coupled to an insertion tool 306, asshown in FIGS. 38 and 39.

Referring to FIGS. 31 and 34-35, spacer 302 is similar to spacer 202,but, instead of a solid posterior portion 222, posterior portion 322 ofspacer 302 includes a gap 325 between two medially directed ends 324,326. Gap 325 allows for spacer 302 to flex after insertion, which mayprovide enhanced mobility for the patient.

Additionally, spacer 302 includes indentations 317, 319 that are largerthan indentations 217, 219 on spacer 202. Similarly, fingers 338, 340 onplate 304 are wider than fingers 238, 240 on plate 204 to accommodatethe larger indentations 317, 319.

Other aspects of spacer 302, plate 304, and insertion tool 306 aresimilar, if not identical, to corresponding aspects of spacer 202, plate204, and insertion tool 206 as discussed above. Those aspects areidentified with element numbers corresponding to spacer 202, plate 204,and insertion tool 206 with respect to spacer 302, plate 304, andinsertion tool 306, respectively.

With respect to a spacer block 390 shown in FIGS. 40 and 41, however,spacer block 390 includes fingers 396, 398 that are insertable intoindentations 317, 319. Other aspects of spacer block 390 are similar, ifnot identical, to corresponding aspects of spacer block 290 as discussedabove.

Instead of plate 304, an alternative plate 304′, shown in FIGS. 41A-41Dcan be provided. Plate 304′ is similar to plate 304, with the additionof a superior extension 393 on the posterior end 394 of plate 304′.Extension 393 increases the overall height of plate 304′ and allowsplate 304′ to be shouldered onto the vertebral body during insertion. Asshown in FIG. 41B, extension 393 can be straight. Alternatively,extension 393 can be angled in a posterior direction.

An alternative embodiment of an intervertebral spacer and plate assembly400 (“assembly 400”) is shown in FIGS. 42-50. In an exemplaryembodiment, assembly 400 can be used for lumbar repair, although thoseskilled in the art will recognize that assembly 400 can be sized forthoracic or cervical repair as well.

Assembly 400 is formed from two separate components, an intervertebralspacer 402 (“spacer 402”) and a plate 404 (“plate 404”). In someembodiments, spacer 402 and plate 404 are not connected to each other,but are instead each separately coupled to an insertion tool 406, asshown in FIGS. 47 and 48. Upon delivery to a surgical site, the spacer402 and plate 404 can be decoupled from one another.

Referring to FIGS. 42-47, spacer 402 is similar to spacer 302, but,instead of holes 260, 262 for insertion of insertion tool 306, lateralsides 416, 418 include a recess 460, 462, respectively. Recesses 460,462 extend anteriorly from indentations 317, 319 toward anterior face456. Each recess 460, 462 includes a plurality of superior-to-inferiorextending slots 464. FIGS. 45 and 46 show two slots 464 in each recess460, 462, although those skilled in the art will recognize that more orless than two slots 464 can be provided.

Additionally, fingers 338, 340 on plate 404 each include a recess 438,440, respectively that extend in an anterior-to-posterior directionalong the length of each respective finger 338, 340. Each recess 438,440 includes a plurality of superior-to-inferior extending slots 464.FIGS. 45 and 46 show two slots 442 in each recess 438, 440, althoughthose skilled in the art will recognize that more or less than two slots442 can be provided.

Other aspects of spacer 402 and plate 404 are similar, if not identical,to corresponding aspects of spacer 302 and plate 304 as discussed above.Those aspects are identified with element numbers corresponding tospacer 302 and plate 304 with respect to spacer 402 and plate 404,respectively.

Insertion tool 406 is shown in FIGS. 47-52. Insertion tool 406 includesa distal end 470 having a first distal finger 472 and a second distalfinger 474 that extends generally parallel to first distal finger 474. Agap between fingers 472, 474 forms a generally U-shaped cavity 476 thatis sized to accept plate 404 therein, as shown in FIGS. 47 and 48. Firstdistal finger 472 includes a plurality of protrusions 478 that fit intorecess 460 and slots 464 on spacer 402 and recess 438 and slots 442 onplate 404. Similarly, second distal finger 474 includes a plurality ofprotrusions 480 that fit into recess 462 and slots 464 on spacer 402 andrecess 440 and slots 442 on plate 404.

A proximal end (not shown) of insertion tool 406 can include a pivotconnection such that the opening of insertion tool 406 at the proximalend splays first distal finger 472 away from second distal finger 474 torelease spacer 402 and plate 404 so that spacer 402 and plate 404 areseparated components.

Referring to FIGS. 51 and 52, spacer block 490 includes slots 492 thatreceive protrusions 478, 480 on insertion tool 406. Other aspects ofspacer block 490 are similar, if not identical, to corresponding aspectsof spacer block 390 as discussed above.

An alternative embodiment of an intervertebral spacer and plate assembly500 (“assembly 500”) is shown in FIGS. 53-63. In an exemplaryembodiment, assembly 500 can be used for lumbar repair, although thoseskilled in the art will recognize that assembly 500 can be sized forthoracic or cervical repair as well.

Assembly 500 is formed from two separate components, an intervertebralspacer 502 (“spacer 502”) and a plate 504 (“plate 504”). In someembodiments, spacer 502 and plate 504 are not connected to each other,but are instead each separately coupled to an insertion tool 506, asshown in FIGS. 58 and 59.

Assembly 500 is similar to assembly 400 except that, instead of havinggap 325 between two medially directed ends 324, 326, spacer 502 has aposterior portion 525 that extends fully between lateral sides 516, 518.Lateral sides 516, 518 include indentations 517, 519 that do not extendmedially as far as indentations 317, 319 respectively, formed in spacer402, as discussed above.

Additionally, referring to FIGS. 62 and 63, a spacer block 590 includesslots 592 that receive protrusions 478, 480 on an insertion tool 4506.

An alternative embodiment of an intervertebral spacer and plate assembly600 (“assembly 600”) is shown in FIGS. 64-67. In an exemplaryembodiment, assembly 600 can be used for lumbar repair, although thoseskilled in the art will recognize that assembly 600 can be sized forthoracic or cervical repair as well.

Assembly 600 is formed from two separate components, an intervertebralspacer 602 (“spacer 602”) and a plate 604 (“plate 604”). Plate 704 isshown in detail in FIGS. 75-78. Plate 602 has a body 610 having agenerally arcuate shape, with generally parallel lateral sides 612, 614.A posterior portion 625, respectively, of each lateral side 612, 614includes an anterior-to-posterior recess 620, 622, respectively. Eachrecess 620, 622 includes a laterally projecting protrusion 624 havingsloped superior and inferior sides (only one protrusion 624 is shown inFIG. 65). Each recess 620, 622 is in communication with a slot 628, 630,respectively that each extends medially. A medial portion 628, 629 ofeach lateral side 612, 614, respectively, include an oblique cutout 616,618.

Plate 604 includes a body 605 having a generally laterally elongateshape, with generally parallel lateral sides 642, 644. Fingers 638, 640extend from lateral sides 642, 644, respectively. Fingers 638, 640 aresized to fit into recesses 620, 622, respectively, in spacer 602. Asshown in FIG. 65, finger 638 includes a cutout 646 formed therein.Although not shown, finger 640 includes a corresponding cutout. Ananterior end of each finger 638, 640 includes a medially extending prong648, 650 that fits into a slot 628, 630, respectively. An anterior face652 of body 605 also includes two spaced apart tangs 654, 656.

Referring to FIG. 66, through-holes 664, 666, 668 are provided in plate604 and are sized to allow a securing screw (not shown) to be insertedtherethrough to secure plate 604 to each of a superior vertebra (notshown) and an inferior vertebra (not shown), between which spacer 602 isbeing inserted. Through-holes 664, 666 each extends in asuperior-to-inferior direction so that their respective screw eachengages and secures to the inferior vertebra, while through-hole 668extends in an inferior-to-superior direction so that its screw engagesand secures the superior vertebra.

Locking screws 670, 672 are each is disposed between respectivethrough-holes 664, 666, 668. Each locking screw 670, 672 has a head 676with a pair of arcuate cutouts 682, 684 that are sized to allow thesecuring screws discussed above to be inserted into through-holes 664,666, 668. During insertion of assembly 600, locking screws 670, 672 arein a configuration relative to plate 604 as shown in FIG. 66. After thesecuring screws secure plate 604 to the superior and inferior vertebra,locking screws 670, 672 are rotated, for example, about 90 degrees, sothat heads 676, 678 each extends over its adjacent securing screws,preventing the securing screws from inadvertently backing out. In someembodiments, the locking screws 670, 672 (upon rotation) can abut a sideof the securing screws to prevent inadvertent backing out.

Assembly 600 is fitted together by aligning fingers 638, 640 and prongs648, 650 on plate 604 with recesses 620, 622 and slots 628, 630,respectively, on spacer 602, which also aligns lateral sides of tangs654, 656 with cutout 616, 618, respectively. Plate 604 is slid down intospacer 602, locking fingers 638, 640 and prongs 648, 650 into recesses620, 622 and slots 628, 630, respectively.

Additionally, protrusion 624 slides into cutout 646. Tangs 654, 656engage cutouts 616, 618, respectively, stabilizing plate 604 withrespect to spacer 602.

Assembly 600 is inserted between adjacent vertebrae as a unit, and,unlike other embodiments of the present invention, remain as a unitafter implantation.

Another alternative embodiment of an intervertebral spacer and plateassembly 700 (“assembly 700”) is shown in FIGS. 68-82. In an exemplaryembodiment, assembly 700 can be used for cervical repair, although thoseskilled in the art will recognize that assembly 400 can be sized forthoracic or lumbar repair as well.

Assembly 700 is formed from two separate components, an intervertebralspacer 702 (“spacer 702”) and a plate 704 (“plate 704”). In someembodiments, spacer 702 and plate 704 are not connected to each other,but are instead each separately coupled to an insertion tool similar toinsertion tool 406, shown in FIGS. 47 and 48.

Referring to FIGS. 72-74, spacer 702 is similar to spacer 402, but,instead of having gap 325 between two medially directed ends 324, 326,spacer 702 has a posterior portion 725 that extends fully betweenlateral sides 716, 718. Recesses 760, 762 extend anteriorly fromposterior portion 725 toward anterior face 756. Each recess 760, 762includes a plurality of superior-to-inferior extending slots 764. FIGS.73 and 74 show two slots 764 in each recess 760, 762, respectively,although those skilled in the art will recognize that more or less thantwo slots 764 can be provided.

Posterior portion 725 includes cutouts 728, 730 to allow securing screws(not shown) to extend therethrough to secure plate 704 to adjacentvertebrae (not shown). When viewed from a posterior-to-anteriordirection, a first cutout 728 is formed in a superior surface 710 and isdefined by side walls 732, 734 and a bottom wall 736. As shown in FIG.72, side walls 732, 734 and bottom wall 736 extend at oblique anglesrelative to each other, although those skilled in the art will recognizethat side walls 732, 734 can extend orthogonally to bottom wall 736.

Similarly, a second cutout 738 is formed in an inferior surface 712 andis defined by side walls 742, 744 and a top wall 746. As shown in FIG.72, side walls 742, 744 and top wall 746 extend at oblique anglesrelative to each other, although those skilled in the art will recognizethat side walls 742, 744 can extend orthogonally to top wall 746.

Plate 704 is shown in detail in FIGS. 75-78. Plate 704 has a body 750having a generally arcuate shape, with generally parallel lateral sides752, 754. Each lateral side 752, 754 includes an anterior-to-posteriorrecess 776, 778, respectively. Each recess 776, 778 is in communicationwith a slot 760, 762 in spacer 702.

Plate 704 also includes through-openings 782, 784 for securing screws(not shown) that are used to secure plate 704 to adjacent vertebrae (notshown). A locking screw 786 can be rotated, for example, about 90degrees after the securing screws have been inserted to keep thesecuring screws from backing out after insertion. When plate 704 isaligned with spacer 702 as shown in FIGS. 79-82, through-opening 782 isaligned with first cutout 728 in spacer 702 and through-opening 784 isaligned with second cutout 730 in spacer 702 so that the securing screwscan pass over or under spacer 702 and into their respective vertebrae.

Also, as shown in FIGS. 81 and 82, when plate 704 is aligned with spacer702 for insertion, recess 776 is aligned with recess 760 and recess 778is aligned with recess 762 so that an insertion tool, similar toinsertion tool 406, can extend through plate 704 and grip spacer 702 forinsertion.

The insertion procedure for assembly 700 can be similar to that as isdescribed above for assembly 400. However, instead of insertion tool 406having protrusions that engage plate 704, such protrusions can beomitted and assembly 700 can rely on friction between plate 704 andinsertion tool 406, as well as between implant 702 and insertion tool406.

An alternative embodiment of an intervertebral spacer and plate assembly800 (“assembly 800”) is shown in FIGS. 83-98. In an exemplaryembodiment, assembly 800 can be used for cervical repair, although thoseskilled in the art will recognize that assembly 800 can be sized forthoracic or lumbar repair as well.

Assembly 800 is formed from two separate components, an intervertebralspacer 802 (“spacer 802”) and a plate 804 (“plate 804”). In someembodiments, spacer 802 and plate 804 are not connected to each other,but instead merely engage each other.

Referring to FIGS. 84 and 86-89, spacer 802 includes a body 808 having asuperior surface 810 and an opposing inferior surface 812. Each ofsuperior surface 810 and inferior surface 812 can have a plurality offixation elements 814 extending outwardly therefrom. While fixationelements 814 are shown as being generally pyramidal in shape, thoseskilled in the art will recognize that fixation elements 814 can beother shapes, such as ribbed, or other suitable shapes. Fixationelements 814 are used to bite into a grip each of adjacent vertebrae(not shown) between which spacer 802 is inserted.

As shown in FIG. 20, body 802 can have a generally oblong shape, withgenerally linear lateral sides 816, 818, connected to each other by ananterior portion 820 and a posterior portion 822, with a generallyisosceles trapezoid interior space 823 defined therebetween that canoptionally be filled with graft material.

Posterior portion 822 includes an arcuate face 824 that extends betweenlateral sides 816, 818. A rounded protrusion 826 extends posteriorlyfrom posterior portion 822. A pair of insertion tool engagement holes828, 829 are each located on opposing sides of protrusion 826. Holes828, 829 can be threaded or unthreaded, and can be through-holes orblind holes. Holes 828, 829 are sized to accept arms of an insertiontool (not shown) for insertion of assembly 800.

Referring now to FIGS. 85 and 90-93, plate 804 includes a body 830having an anterior surface 832 and an opposing posterior surface 834.Referring to FIGS. 90 and 91, plate 804 can have a generally “X” shape,with left and right superior arms 836, 838, respectively, and left andright inferior arms 840, 842, respectively. Superior arms 836, 838include through-openings 844, 846 that are angled in a superiordirection to allow screws (not shown) to be inserted therethrough tosecure plate 804 to a superior vertebra (not shown). Similarly, inferiorarms 840, 842 include through-openings 848, 850 that are angled in aninferior direction to allow securing screws (not shown) to be insertedtherethrough to secure plate 804 to an inferior vertebra (not shown).

Referring to FIG. 90, locking screws 852, 854, 856, 858 are eachdisposed adjacent to a respective through-opening 844, 846, 848, 850.Each locking screw 852, 854, 856, 858 has a head 860 with an arcuatecutout 862, respectively, that is sized to allow the securing screwsdiscussed above to be inserted into through-openings 844, 846, 848, 850.During insertion of assembly 800, locking screws 852, 854, 856, 858 arein a configuration relative to plate 804 as shown in FIG. 95. After thesecuring screws secure plate 804 to the superior and inferior vertebra,locking screws 852, 854, 856, 858 are rotated, for example, about 90degrees, so that heads 860 each extends over its adjacent securingscrews, preventing the securing screws from inadvertently backing out.

Plate 804 also includes a centrally located posterior recess 870. Asshown in FIG. 90, recess 870 can be generally oblong in shape, althoughthose skilled in the art will recognize that recess 870 can be othershapes. Recess 870 accepts a prong on an insertion device (not shown)for insertion of assembly 800.

Referring to FIG. 91, anterior surface 8732 of plate 804 includes acentrally located concave recess 874 that accepts protrusion 826, asshown in FIG. 98. Protrusion 826 rides within recess 874, forming anarticulating joint that allows plate 804 to pivot relative to body 802,providing some flexibility for the patient after assembly 800 isimplanted.

FIGS. 83 and 95-98 show assembly 800. While plate 804 is butted upagainst spacer 802 to form a coupled construct, plate 804 is not rigidlyconnected to spacer 802 so that spacer 802 and plate 804 remainseparate, independent components throughout insertion and afterinsertion into the patient.

An alternative embodiment of an intervertebral spacer and plate assembly900 (“assembly 900”) is shown in FIGS. 99-113. In an exemplaryembodiment, assembly 900 can be used for cervical repair, although thoseskilled in the art will recognize that assembly 900 can be sized forthoracic or lumbar repair as well.

Assembly 900 is formed from two separate components, an intervertebralspacer 902 and a plate 904. Spacer 902 and plate 904 are never connectedto each other, but instead merely engage each other.

Referring to FIGS. 99 and 102-105, spacer 902 includes a body 908 havinga superior surface 910 and an opposing inferior surface 912. Each ofsuperior surface 910 and inferior surface 912 can have a plurality offixation elements 914 extending outwardly therefrom. While fixationelements 914 are shown as being generally pyramidal in shape, thoseskilled in the art will recognize that fixation elements 914 can beother shapes, such as ribbed, or other suitable shapes. Fixationelements 914 are used to bite into a grip each of adjacent vertebrae(not shown) between which spacer 902 is inserted.

As shown in FIG. 103, body 902 can have a generally oblong shape, withgenerally linear lateral sides 916, 918, connected to each other by ananterior portion 920 and a posterior portion 922, with a generallyisosceles trapezoid interior space 923 defined therebetween that canoptionally be filled with graft material.

Posterior portion 922 includes an arcuate face 924 that extends betweenlateral sides 916, 918. A generally centrally located insertion toolengagement hole 928 extends through posterior portion 922. Hole 928 canbe threaded, as shown in FIG. 100, or unthreaded. Hole 928 is sized toan insertion tool (not shown) for insertion of assembly 900.

A pair of plate engagement slots 931, 932 are each located on opposingsides of hole 928. Slots 931, 932 are blind holes and are generallyrectangular in shape, with rounded corners. Slots 931, 932 are sized toaccept posterior protrusions from plate 904, as is discussed below.

Referring now to FIGS. 101 and 106-109, plate 904 includes a body 930having an anterior surface 933 and an opposing posterior surface 934.Referring to FIGS. 108 and 109 and 91 plate can have a generally“rhomboid” shape, with a right superior arm 936 and a left inferior arm940. Superior arm 936 includes a through-opening 944 that is angled in asuperior direction to allow a screw (not shown) to be insertedtherethrough to secure plate 904 to a superior vertebra (not shown).Similarly, inferior arm 940 includes a through-opening 948 that isangled in an inferior direction to allow a securing screw (not shown) tobe inserted therethrough to secure plate 904 to an inferior vertebra(not shown).

Referring to FIG. 108, locking screws 952, 954 are each disposedadjacent to a respective through-opening 944, 948. Each locking screw952, 954 has a head 960 with an arcuate cutout 962, respectively, thatis sized to allow the securing screws discussed above to be insertedinto through-openings 944, 948. During insertion of assembly 900,locking screws 952, 954 are in a configuration relative to plate 904 asshown in FIG. 108. After the securing screws secure plate 904 to thesuperior and inferior vertebra, locking screws 952, 954 are rotated, forexample, about 90 degrees, so that heads 960 each extends over itsadjacent securing screws, preventing the securing screws frominadvertently backing out.

Plate 904 also includes a centrally located through-opening 970. Asshown in FIG. 108, through-opening 970 can be generally circular inshape, although those skilled in the art will recognize thatthrough-opening 970 can be other shapes. Through-opening 970 isunthreaded and allows an insertion device (not shown) to passtherethrough for engagement with hole 928 in spacer 902 for insertion ofassembly 900.

Referring still to FIG. 108, a posterior surface 972 of plate 904includes a pair of diametrically opposed slots 974, 976 that extend atan oblique angle away from through-opening 970. Slots 974, 976 accept aprong of an insertion instrument (not shown) during implantation ofassembly 900, allowing the insertion instrument to be placed into slots974, 976 so that plate 904 is held rigidly on the insertion instrumentwithout being able to rotate.

Referring now to FIGS. 106, 107, and 109, an anterior surface 980 ofplate 904 includes a pair of diametrically opposed protrusions 982, 984that are sized and located to fit into plate engagement slots 931, 932.A posterior end of locking screws 952, 954 also extends outwardly fromplate engagement slots 931, 932 as well.

FIGS. 99 and 110-113 show assembly 900. While plate 904 is butted upagainst spacer 902 to form a coupled construct, plate 904 is notconnected to spacer 902 so that spacer 902 and plate 904 remain separatecomponents throughout insertion and after insertion into the patient.

FIGS. 114-116 show an alternative plate 1004 that can be used withspacer 902 to form an assembly 1000. Plate 1004 has a generallyrectangular shape with a centrally located through-opening 1070. Asshown in FIG. 114, through-opening 1070 can be generally circular inshape, although those skilled in the art will recognize thatthrough-opening 1070 can be other shapes. Through-opening 1070 isunthreaded and allows an insertion device (not shown) to passtherethrough for engagement with hole 928 in spacer 902 for insertion ofassembly 1000.

Plate 1004 has left and right superior through-openings 1044, 1046 thatare angled in a superior direction to allow screws (not shown) to beinserted therethrough to secure plate 1004 to a superior vertebra (notshown). Similarly, plate 1004 has left and right inferiorthrough-openings 1048, 1050 that are angled in an inferior direction toallow securing screws (not shown) to be inserted therethrough to secureplate 1004 to an inferior vertebra (not shown).

Locking screws 1052, 1054, 1056, 1058 are each disposed adjacent to arespective through-opening 1044, 1046, 1048, 1050. Each locking screw1052, 1054, 1056, 1058 has a head 1060 with an arcuate cutout 1062,respectively, that is sized to allow the securing screws discussed aboveto be inserted into through-openings 1044, 1046, 1048, 1050. Duringinsertion of assembly 1000, locking screws 1052, 1054, 1056, 1058 are ina configuration relative to plate 1004 as shown in FIG. 114. After thesecuring screws secure plate 904 to the superior and inferior vertebra,locking screws 1052, 1054, 1056, 1058 are rotated, for example, about 90degrees, so that heads 1060 each extends over its adjacent securingscrews, preventing the securing screws from inadvertently backing out.

A posterior surface 1072 of plate 1004 also includes a pair of superiorand inferior slots 1074, 1076 on opposing sides of through-opening 1070.Slots 1074, 1076 accept a prong of an insertion instrument (not shown)during implantation of assembly 1000, allowing the insertion instrumentto be placed into slots 1074, 1076 so that plate 1004 is held rigidly onthe insertion instrument without being able to rotate.

Referring now to FIG. 117, an alternative embodiment of anintervertebral spacer and plate assembly 1100 (“assembly 1100”) isshown. Assembly 1100 includes a spacer 1102 and a plate 1104.

Plate 1102 has a body 1108 that includes a posterior surface 1110.Posterior surface 1110 includes a central through-opening 1112 that issized to accept an insertion instrument 1106. Through-opening 1112 isthreaded to match threads 1114 on a distal end 1116 of insertioninstrument 1106. Posterior surface 1110 also includes a pair of concaverecesses 1120, 1122, one on either side of through-opening 1112.

Plate 1104 has a body 1130 that includes an anterior surface 1132 formating with posterior surface 1110 of spacer 1102. Body 1130 includes athrough-opening 1134 that extends posteriorly-to-anteriorly through thecenter of body 1130. Through-opening 1134 has a larger diameter thanthrough-opening 1112 in spacer 1102 to allow distal end 1116 ofinsertion instrument 1106 to pass therethrough.

Anterior surface 1132 of body 1130 also includes a pair of convexprotrusions 1140, 1142, one on either side of through-opening 1134 thatextend into recesses 1120, 1122, respectively, when plate 1104 is buttedagainst spacer 1102, forming a solid construct.

Referring now to FIG. 118, an alternative embodiment of anintervertebral spacer and plate assembly 1200 (“assembly 1200”) isshown. Assembly 1200 includes a spacer 1202 and a plate 1204.

Plate 1202 has a body 1208 that includes a posterior surface 1210.Posterior surface 1210 includes a central recess 1212. Posterior surface1210 also includes a pair of threaded recesses 1220, 1222, one on eitherside of central recess 1212.

Plate 1204 includes a body 1230 having an anterior surface 1232. Aprotrusion 1234 extends anteriorly from anterior surface 1232 and issized to fit into central recess 1212. Body 1230 also includes a pair oflateral through-holes 1236, 1238 that extend through body 1230 and alignwith threaded recesses 1220, 1222 when protrusion 1234 is inserted intocentral recess 1212.

To insert assembly 1200 into a patient, an insertion instrument (notshown) having two prongs is inserted through through-holes 1236, 1238 inplate 1204 and threaded into threaded recesses 1220, 1222 in plate 1204.Assembly 1200 is inserted into plate 1204 is secured to a patient, thenthe insertion tool is unthreaded from threaded recesses 1220, 1222 andremoved from assembly 1200.

Referring now to FIG. 119, an alternative embodiment of anintervertebral spacer and plate assembly 1300 (“assembly 1300”) isshown. Assembly 1300 includes a spacer 1302 and a plate 1304. Spacer1302 includes a body 1308 having a central void 1309 formed therein. Aposterior side 1310 of spacer 1302 includes a pair of through-passages1312, 1314 into void 1309.

Plate 1304 includes a pair of fingers 1320, 1322, each of which extendsinto one of through-passages 1312, 1314 and into void 1309. When twoprongs of an insertion device (not shown) are inserted intothrough-passages 1312, 1314, fingers 1320, 1322 splay open, temporarilysecuring plate 1304 to spacer 1302 for insertion. After insertion, whenthe insertion device is removed, fingers “un-splay” so that plate 1304is no longer secured to spacer 1302 and spacer 1302 and plate 1304 aretwo separate entities.

Referring now to FIG. 119, an alternative embodiment of anintervertebral spacer and plate assembly 1300 (“assembly 1300”) isshown. Assembly 1300 includes a spacer 1302 and a plate 1304. Spacer1302 includes a body 1308 having a central void 1309 formed therein. Aposterior side 1310 of spacer 1302 includes a pair of through-passages1312, 1314 into void 1309.

Plate 1304 includes a pair of fingers 1320, 1322, each of which extendsinto one of through-passages 1312, 1314 and into void 1309. When twoprongs of an insertion device (not shown) are inserted intothrough-passages 1312, 1314, fingers 1320, 1322 splay open, temporarilysecuring plate 1304 to spacer 1302 for insertion. After insertion, whenthe insertion device is removed, fingers “un-splay” so that plate 1304is no longer secured to spacer 1302 and spacer 1302 and plate 1304 aretwo separate entities.

Referring now to FIG. 120, an alternative embodiment of anintervertebral spacer and plate assembly 1400 (“assembly 1400”) isshown. Assembly 1400 includes a spacer 1402 and a plate 1404. Spacer1402 includes a body 1408. A posterior side 1410 of spacer 1302 includesa pair of blind passages 1412, 1414 extending into body 1408. Each ofblind passages 1412, 1414 widens to a receiving portion 1416, 1418,respectively, in a posterior-to-anterior direction.

Plate 1404 includes a pair of through-passages 1420, 1422 extendingparallel to each other in a posterior-to-anterior direction such that,when plate 1404 is aligned with spacer 1402, passage 1420 aligns withpassage 1412 and passage 1422 aligns with passage 1414.

An insertion device 1406 includes two parallel hollow prongs 1430, 1432.Each prong 1430, 1432 is split posteriorly into two half portions 1430a, 1430 b and 1432 a, 1432 b, each portion 1430 a, 1430 b, 1432 a, 1432b having a lip.

When prongs 1430, 1432 of insertion device 1406 are inserted throughthrough-passages 1420, 1422 and into blind passages 1412, 1414,respectively, and rods (not shown) are inserted through prongs 1430,1432, prong half portions 1430 a, 1430 b and 1432 a, 1432 b splay apartso that the lips on prongs 1430, 1432 splay open and are retained withinreceiving portions 1416, 1418, respectively, temporarily securing plate1404 to spacer 1402 for insertion. After insertion, when the insertiondevice is removed, fingers “un-splay” so that plate 1404 is no longersecured to spacer 1402 and spacer 1402 and plate 1404 are two separateentities.

Referring now to FIG. 121, an alternative embodiment of anintervertebral spacer and plate assembly 1500 (“assembly 1500”) isshown. Assembly 1500 includes a spacer 1502 and a plate 1504. Spacer1502 includes a body 1508 having a central void 1509 formed therein. Aposterior side 1510 of spacer 1502 includes a pair of through-passages1512, 1514 into void 1509.

Plate 1504 includes parallel through-passages 1516, 1518 extendingparallel to each other in a posterior-to-anterior direction such that,when plate 1504 is aligned with spacer 1502, passage 1516 aligns withpassage 1412 and passage 14221518 aligns with passage 1514.

Insertion device 1506 includes a pair of fingers 1520, 1522, each ofwhich extends through one of through-passages 1516, 1518 and one ofthrough-passages 1512, 1514 and into void 1509. Each finger 1520, 1522includes a laterally extending lip 1524, 1526, respectively.

When two prongs of an insertion device (not shown) are inserted intothrough-passages 1516, 1518 and 1512, 1514, with the prongs on medialsides of each of fingers 1520, 1522, fingers 1520, 1522 are biasedlaterally so that lips 1524, 1526 engage the posterior wall of void1509, temporarily securing plate 1504 to spacer 1502 for insertion.After insertion, when the insertion device 1506 is removed, fingers1520, 1522 bias back toward each other so that plate 1504 is no longersecured to spacer 1502 and spacer 1502 and plate 1504 are two separateentities.

Referring now to FIG. 122, an alternative embodiment of anintervertebral spacer and plate assembly 1600 (“assembly 1600”) isshown. Assembly 1600 includes a spacer 1602 and a plate 1604. Spacer1602 includes a body 1608. A posterior side 1610 of spacer 1602 includesa blind slot 1612 extending into body 1608. Slot 1612 includes lateralsidewalls 1614, 1616.

Plate 1604 includes a tab 1620 sized to fit into slot 1612 with lateralspace on either side of tab 1620 to accommodate fingers 1622, 1624.Biased fingers 1622, 1624 are pivotally connected to spacer 1602 withanterior ends 1626, 1628 having a plurality of laterally extendingfingers 1630. Posterior ends 1632, 1634 of fingers 1622, 1624 areengageable by an insertion device (not shown)

During insertion, fingers 1622, 1624 are against lateral sidewalls 1614,1616 of slot 1612 so that plate 1604 is engaged with spacer 1602.Fingers 1630 compress toward their respective fingers 1622, 1624,wedging plate 1604 into spacer 1602. After assembly 1600 is inserted,the insertion device is removed, allowing fingers 1622, 1624 to biasaway from sidewalls 1614, 1616, respectively, releasing spacer 1602 fromplate 1604.

Referring now to FIGS. 123-125, an alternative embodiment of anintervertebral spacer and plate assembly 1700 (“assembly 1700”) isshown. Assembly 1700 includes a spacer 1702 and a plate 1704. Spacer1702 includes a body 1708 having a central void 1709 formed therein. Asuperior surface 1710 of spacer 1702 includes a central slot 1712extending along a posterior surface 1714 to void 1709. Similarly, aninferior surface 1720 includes a corresponding slot 1722.

Referring to FIG. 123, plate 1704 includes a slot 1730 extending along atop surface 1732 thereof and a slot 1734 extending along a bottomsurface 1736 thereof. Plate 1704 includes a pair of screw opening 1740,1742 and a centrally located blocking screw 1744. An alternativeembodiment of a plate 1704′, shown in FIG. 124, uses multiple blockingscrews 1744′, 1746′, each for an individual screw opening 1740′, 1742′,with locking screws 1744′, 1746′ disposed laterally away from a centerof plate 1704′ to allow plate 1704′ to be thinner than plate 1704 andstill be able to secure screws (not shown) in screw openings 1740′,1742′.

FIG. 125 shows in insertion device 1706 gripping both spacer 1702 andeither plate 1704 or plate 1704′. Insertion device 1706 extends throughslots 1730, 1712 and slots 1734, 1722, securing spacer 1702 and plate1704, 1704′ to securing device 1706. After insertion, insertion device1706 is slid posteriorly, decupling spacer 1702 and plate 1704, 1704′.

Referring to FIGS. 126 and 127, an alternative embodiment of anintervertebral spacer and plate assembly 1800 (“assembly 1800”) isshown. Assembly 1800 includes a spacer 1802 and a plate 1804. Spacer1802 includes a body 1810 having a posterior portion 1812. Posteriorportion 1812 includes a space 1814 that is sized to receive plate 1804.Plate 1804 can be inserted into space 1814 from a posterior direction orfrom a superior direction.

Spacer 1802 can include connections for an insertion device (not shown)similar to that disclosed with respect to spacer 102, described above.Assembly 1800 can be inserted as a unit and then, after insertion, theinsertion device is removed and spacer 1802 and plate 1804 remain asseparate components in the patient's spinal column.

Referring to FIGS. 128-130 an alternative embodiment of anintervertebral spacer and plate assembly 1900 (“assembly 1900”) isshown. Assembly 1900 includes a spacer 1902 and a plate 1904 or plate1904′. Spacer 1902 includes a body 1910 having a posterior portion 1912.Posterior portion 1912 includes a threaded opening 1914 that is sized toreceive an insertion tool (not shown). Each of plates 1904, 1904′include a threaded connection 1920, 1920′ extending therethrough.Threaded connections 1920, 1920′ accept a threaded insertion device (notshown) that extends though plate 1904, 1904′ and into threaded opening1914 in plate 1904. The threaded connection between the insertion deviceand spacer 1902 and plate 1904, 1904′ can be loose to provide forarticulation during insertion, similar to the movement of a joystick.Once assembly 1900 is inserted, the insertion device is removed, andspacer 1902 and plate 1904, 1904′ remain as separate components in thepatient's spinal column.

FIG. 131 is a top perspective view of a spacer and plate assemblyaccording to a nineteenth embodiment. The spacer and plate assembly 2000comprises a spacer 2002 and a plate 2004. The spacer 2002 and plate 2004are advantageously configured to be delivered to a surgical site via aninsertion tool. In the present embodiment, the insertion tool comprisesa threaded coupling shaft 2070 (shown in FIG. 136) that holds both thespacer 2002 and the plate 2004 thereon. Once delivered, the insertiontool can be removed, thereby leaving the spacer 2002 and plate 2004 inplace. At the surgical site, the spacer 2002 and plate 2004 are leftdecoupled and unfixed to one another.

The spacer 2002 comprises a body 2008 having a superior surface 2010 andan inferior surface 2012, each having one or more fixation elements 2014in the form of protrusions, pyramids, or ribbing. The one or morefixation elements 2014 advantageously serve to grip bone in an adjacentvertebral body. The body 2008 of the spacer 2002 comprises an anteriorportion 2020 and a posterior portion 2022 separated by lateral sides2016, 2018. In some embodiments, the body 2008 comprises a c-shape,wherein the lateral sides 2016, 2018 form curved arms that surround aninner space 2023 for receiving graft material therein. The inner spacer2023 is surrounded by an inner wall or surface 2027 that curves along aninterior of the spacer 2002.

As shown in FIG. 131, a bore 2026 is formed along the inner surface2027. In some embodiments, the bore 2026 is a threaded bore. Thethreaded bore 2026 is configured to receive a threaded distal end 2072of a coupling shaft 2070 of an insertion tool (shown in FIG. 136). Insome embodiments, the threaded bore 2026 extends from the inner surface2027 completely though the anterior portion 2020 of the spacer 2002,while in other embodiments, the threaded bore 2026 extends from theinner surface 2027 only partially through the anterior portion 2020 ofthe spacer 2002.

As shown in FIG. 131, the body 2008 of the spacer 2002 includes firstand second recesses or indentations 2017, 2019. Indentation 2017 isformed along lateral side 2016, while indentation 2019 is formed alonglateral side 2018. The indentations 2017, 2019 serve to receive fingers2038, 2040 of the plate 2004, as shown in FIG. 136. The indentations2017, 2019 advantageously help to stabilize the spacer 2002 and plate2004 relative to one another when they are operatively coupled via theinsertion tool. The spacer 2002 can be formed of both synthetic andnatural material. In some embodiments, the spacer 2002 is formed ofbone, PEEK or titanium.

The plate 2004 comprises a body 2030 having a superior surface 2032 andan inferior surface 2034. Portions of the superior surface 2032 andinferior surface 2034 include stabilizer elements 2036. In someembodiments, the stabilizer elements comprise protrusions, pyramids, orribbing that are advantageously designed to provide torsionalstabilization.

The plate 2004 further comprises a posterior portion comprisingthrough-holes 2064, 2066, 2068 for receiving fasteners therein. In thepresent embodiment, the plate 2004 further includes locking screws 2070,2072, 2074, each associated with one of the through-holes 2064, 2066,2068. The locking screws 2070, 2072, 2074 each have cut-away regionsthat allow for entry or removal of fasteners through the plate 2004 inone configuration, but prevent backout of the fasteners when rotatedinto a second configuration. In some embodiments, the plate 2004 furthercomprises a pair of non-threaded bores 2044, 2046, each of differentsizes. Non-threaded bore 2044 is configured to receive extension 2063 ofinsertion tool 2006 (shown in FIG. 140A), while non-threaded bore 2044is configured to receive coupling shaft 2070 of insertion tool 2006(also shown in FIG. 140A). Non-threaded bore 2044 comprises a partialbore that is not fully enclosed. Non-threaded bore 2044 bordersthrough-hole 2064. Non-threaded bore 2046 comprises a full bore that isfully enclosed. In some embodiments, non-threaded bore 2046 comprises asquare, while in other embodiments, non-threaded bore 2046 comprises asquare with rounded corners or edges.

The plate 2004 further comprises a pair of arms or fingers 2038, 2040extending from the posterior portion of the plate 2004. The fingers2038, 2040 comprise extensions that are configured to be received in theindentations 2017, 2019 of the spacer 2002 when the insertion tool 2006holds them together. In some embodiments, the fingers 2038, 2040 areconfigured to include stabilizer elements 2036 thereon. Advantageously,the fingers 2038, 2040 of the plate 2004 are configured to abut surfacesof the spacer 2002 without tightly gripping the spacer 2002, therebyallowing the spacer 2002 to be decoupled from the plate 2004 upondelivery to a surgical site. By providing a decoupled plate 2004 andspacer 2002, each can advantageously be delivered on their own, ortogether via an insertion tool. In some embodiments, the plate 2004further comprises windows 2039, which are formed on each of the fingers2038, 2040. The windows 2039 advantageously provide surgeons openingsfor visualization, so that they can confirm fusion is taking place.

FIG. 132 is a top view of the assembly shown in FIG. 131. From thisview, one can see the contours of the spacer 2002 and plate 2004. Insome embodiments, the spacer 2002 comprises a c-shaped member having aspace 2023 for receiving graft material therein. In some embodiments,the plate 2004 comprises fingers 2038, 2040 configured to be received inindentations 2017, 2019 of the spacer 2002. As shown in FIG. 132, thefingers 2038, 2040 have rounded edges that are configured to abutsurfaces of the spacer 2002.

FIG. 133 is a side view of the assembly shown in FIG. 131. From thisview, one can the side contours of the spacer 2002 and plate 2004. Insome embodiments, the spacer 2002 comprises one or more chamfers 2029that allow for clearance of bone fasteners or screws that are insertedthrough the plate 2004. In some embodiments, the spacer 2002 comprises apair of chamfers 2029, one found on each of the lateral sides 2016, 2018of the spacer 2002. In some embodiments, the plate 2004 comprises one ormore windows 2039 that provide for visualization. In some embodiments,the windows 2039 are circular. In other embodiments, the windows 2039are non-rounded, such as square or rectangular.

FIG. 134 is a posterior view of the assembly shown in FIG. 131. Fromthis view, one can see the through-holes 2064, 2066, 2068 formed in theplate 2004 for receiving bone fasteners or screws therein. In someembodiments, the through-holes 2064, 2066 are configured to receive bonefasteners in a downward direction, while through-hole 2068 is configuredto receive a bone fastener in an upward direction. Each of thethrough-holes 2064, 2066, 2068 is associated with a locking screw 2070,2072, 2074 with cut-away regions. In some embodiments, locking screws2070, 2074 are positioned adjacent non-threaded bore 2044, while lockingscrew 2072 is positioned adjacent non-threaded bore 2046.

FIG. 135 is a posterior view of the spacer shown in FIG. 131. The spacer2002 comprises an inner curved wall 2027 that forms a perimeter aroundinner space 2023. Along the inner wall 2023 is formed a threaded bore2026 for receiving a coupling shaft 2070 of an insertion tool 2006(shown in FIG. 136).

FIG. 136 is a top perspective view of the assembly shown in FIG. 131attached to an insertion tool. In the present figure, the insertion tool2006 is provided with break lines to show internal details. One skilledin the art will appreciate that the insertion tool 2006 does not havesuch break lines in operation, and that the break lines are to aid inthe description of the insertion tool 2006. The insertion tool 2006comprises an outer shaft 2060 that is coupled to an abutting end 2062 onone end and a handle 2065 on the other end.

The outer shaft 2060 comprises a hollow interior that is configured toreceive a coupling shaft 2070 therein. The coupling shaft 2070 comprisesa shaft having a threaded distal end 2072. The coupling shaft 2070 isconfigured to extend through the non-threaded bore 2046 in the plate2004 (shown in FIG. 131) before extending through the threaded bore 2026of the spacer 2002 (also shown in FIG. 131). The coupling shaft 2070advantageously operatively couples the spacer 2002 and plate 2004 duringdelivery to a surgical site. In some embodiments, the coupling shaft2070 can be received in a proximal opening 2068 of the insertion tool2006, as shown in FIG. 136. A driver (e.g., a hex driver) can be used torotate the coupling shaft 2070. This rotation allows the coupling shaft2070 to threadingly mate with the threaded bore 2026 of the spacer 2002.

The abutting end 2062 of the insertion tool 2006 comprises a distal endof the insertion tool 2006. The abutting end 2062 of the insertion tool2006 is capable of abutting the plate 2004. As shown in FIG. 140B,extension 2063 and coupling shaft 2070 can extend outwardly from theabutting end 2062.

The handle 2065 of the insertion tool 2006 comprises a gripping surface.A surgeon is capable of gripping the handle 2065 and rotating thecoupling shaft 2070 within the insertion tool 2006. In some embodiments,the handle 2065 comprises a proximal opening 2068 for receiving thecoupling shaft 2070 therethrough.

FIG. 137 is a top view of the assembly shown in FIG. 131 attached to aninsertion tool. From this view, one can see how the outer shaft 2060 ofthe insertion tool 2006 and thus, the coupling shaft 2070, are offsetfrom a middle axis of the spacer 2002 and plate 2004.

FIG. 138 is a side view of the assembly shown in FIG. 131 attached to aninsertion tool. From this view, one can see how the spacer 2002 andplate 2004 are inserted into a surgical site. The spacer 2002 comprisesa tapered leading end that aids in insertion of the assembly.

FIG. 139 is a bottom view of the assembly shown in FIG. 131 attached toan insertion tool. From this view, one can see how the spacer 2002 ischamfered on each of its lateral sides 2016, 2018, thereby providingclearance for bone screws or fasteners that are inserted through theplate 2004.

FIGS. 140A-140C illustrate the insertion tool being attached to thespacer and plate assembly in accordance with some embodiments. FIG. 140Aillustrates the insertion tool 2006 prior to insertion of the couplingshaft 2070 in the outer shaft 206. FIG. 140B illustrates the insertiontool 2006 with the coupling shaft 2070 inserted in the outer shaft 206.In the present figure, the insertion tool 2006 is not yet engaged withthe plate 2004 or spacer 2002. FIG. 140C illustrates the insertion tool2006 engaged with the plate 2004 via the coupling shaft 2070, but notyet engaged with the spacer 2002. While not shown in FIGS. 140A-140C,the threaded distal end 2072 of the coupling shaft 2070 will engage thethreaded bore 2026 of the spacer 2002, thereby operatively coupling thespacer 2002 and plate 2004 during delivery to a disc space. Oncedelivered, bone fasteners can be inserted into the plate 2004 to therebyfix the plate 2004 to one or more adjacent vertebrae. The insertion tool2006 can then be removed. Upon removal of the insertion tool 2006, theplate 2004 and spacer 2002 are left in the surgical site, uncoupled toone another.

FIG. 141 is a top perspective view of a spacer and plate assemblyaccording to a twentieth embodiment. The spacer and plate assembly 2100comprises a plate 2104 having novel gripping components 2142 that aredesigned to have a first “neutral” configuration whereby a spacer 2102is ungripped and a second “non-neutral” configuration whereby a spacer2102 is gripped. While in this second configuration, an insertion toolcan advantageously deliver the spacer 2102 and plate 2104 together intoa surgical site. Once at the surgical site, the spacer 2102 and plate2104 can be decoupled by changing the gripping components 2142 back tothe first neutral configuration.

The spacer and plate assembly 2100 comprises a spacer 2102 and a plate2104. The spacer 2102 comprises a body 2108 having a superior surface2110 and an inferior surface 2112, each having one or more fixationelements 2114 in the form of protrusions, pyramids, or ribbing. The oneor more fixation elements 2114 advantageously serve to grip bone in anadjacent vertebral body. The body 2108 of the spacer 2102 comprises ananterior portion 2120 and a posterior portion 2122 separated by lateralsides 2116, 2118. In the present embodiment, the body 2108 comprises anenclosed d-shape, wherein the lateral sides 2116, 2118 form curved armsthat surround an inner space 2123 for receiving graft material therein.The inner spacer 2123 is surrounded by an inner wall or surface 2127that curves along an interior of the spacer 2102.

As shown in FIG. 131, the body 2108 of the spacer 2102 includes firstand second recesses or indentations 2117, 2119. Indentation 2117 isformed along lateral side 2116, while indentation 2119 is formed alonglateral side 2118. The indentations 2117, 2119 serve to receive fingers2138, 2140 of the plate 2104, as shown in FIG. 142. The indentations2117, 2119 advantageously help to stabilize the spacer 2102 and plate2104 relative to one another when they are operatively coupled via theinsertion tool. The spacer 2102 can be formed of both synthetic andnatural material. In some embodiments, the spacer 2102 is formed ofbone, PEEK or titanium.

The plate 2104 comprises a body 2130 having a superior surface 2132 andan inferior surface 2134. Portions of the superior surface 2132 andinferior surface 2134 include stabilizer elements 2136. In someembodiments, the stabilizer elements comprise protrusions, pyramids, orribbing that are advantageously designed to provide torsionalstabilization.

The plate 2104 further comprises a posterior portion comprisingthrough-holes 2164, 2166, 2168 for receiving fasteners therein. In thepresent embodiment, the plate 2104 further includes locking screws thatare received in openings 2171, 2173. The locking screws each havecut-away regions that allow for entry or removal of fasteners throughthe plate 2104 in one configuration, but prevent backout of fastenerswhen rotated into a second configuration. In some embodiments, theposterior portion of the plate 2104 comprises recesses 2145, 2147 thatare configured to receive gripping components 2140, 2142 therein. Thegripping components 2140, 2142 comprise c-shaped bodies having slots2144, 2146 formed therein. The slots 2144, 2146 enable to the grippingcomponents 2140, 2142 to be compressed and received in the recesses2145, 2147. The gripping components 2140, 2142 are capable of being in aneutral configuration (shown in FIG. 146A), whereby the spacer 2102 isnot compressed. The gripping components 2140, 2142 are further capableof being in a non-neutral configuration (shown in FIG. 147A), wherebythe spacer 2102 is compressed. In the neutral configuration, the plate2104 is not coupled to the spacer 2102, while in the non-neutralconfiguration, the plate 2104 is coupled to the spacer 2102.Accordingly, by providing these configurations, a surgeon canadvantageously choose to deliver the spacer 2102 and plate 2104 to asurgical site together or separately one at a time, depending on theneeds of a patient.

One or more holders, instruments or tools can move the grippingcomponents 2140, 2142 from a neutral configuration to a non-neutralconfiguration. In some embodiments, the gripping components 2140, 2142permit the plate 2104 to grip the spacer 2102 temporarily. In someembodiments, a single holder or insertion tool can be inserted into thespaces 2147, 2149 adjacent the gripping components 2140, 2142 (shown inFIGS. 146A and 147A), thereby moving the gripping components 2140, 2142into a non-neutral configuration. In the non-neutral configuration, thegripping components 2140, 2142 of the plate 2104 apply compression onthe spacer 2102, thereby temporarily coupling the plate 2104 to thespacer 2102. With the plate 2104 temporarily coupled to the spacer 2102,the insertion tool can deliver the plate 2104 and spacer 2102 to asurgical site. One or more bone fasteners can be inserted into the plate2104 to attach the plate 2104 to one or more adjacent vertebrae. Withthe plate 2104 and spacer 2102 in the surgical site, the insertion toolcan be retracted from the spaces 2147, 2149, thereby allowing thegripping components 2140, 2142 to spring back into the neutral position.With the gripping components 2140, 2142 in the neutral position, theplate 2104 is no longer coupled to the spacer 2102.

The plate 2104 further comprises a pair of arms or fingers 2138, 2140extending from the posterior portion of the plate 2104. The fingers2138, 2140 comprise extensions that are configured to be received in theindentations 2117, 2119 of the spacer 2102. In some embodiments, thefingers 2138, 2140 are configured to include stabilizer elements 2136thereon. Advantageously, the fingers 2138, 2140 of the plate 2104 areconfigured to abut surfaces of the spacer 2102 without tightly grippingthe spacer 2102, thereby allowing the spacer 2102 to be decoupled fromthe plate 2104 if desired upon delivery to a surgical site. By providinga decoupled plate 2104 and spacer 2102, each can advantageously bedelivered on their own, or together via one or more insertion tools.

FIG. 142 is a top view of the assembly shown in FIG. 141. From thisview, one can see how the inner space 2123 of the spacer 2102 iscompleted enclosed by the inner wall 2127 of the spacer 2102. In someembodiments, only a single through hole 2168 is upwardly angled.

FIG. 143 is a side view of the assembly shown in FIG. 141. From thisview, one can see how the gripping components 2140, 2142 are capable ofbeing received in the recesses 2145, 2147 formed in the plate 2104. Insome embodiments, the gripping components 2140, 2142 are capable ofbeing snapped into the plate 2104.

FIG. 144 is a bottom view of the assembly shown in FIG. 141. As shown inthe figure, a pair of through holes 2164, 2166 are downwardly angled.

FIG. 145 is a posterior view of the assembly shown in FIG. 141. Fromthis view, one can see each of the through holes 2164, 2166, 2168 forreceiving bone screws or fasteners, as well as the locking screws 2170,2172 that help prevent back out of bone screws or fasteners from thethrough holes 2164, 2166, 2168. In some embodiments, locking screw 2170is adjacent through holes 2164, 2168, while locking screw 2172 isadjacent through holes 2166, 2168.

FIGS. 146A-146C illustrate the spacer and plate assembly with thegripping features of the plate in a neutral position in accordance withsome embodiments. In the neutral position, the gripping components 2140,2142 of the plate 2104 are generally parallel to one another and do notcompress the spacer 2102. In this position, the plate 2104 and spacer2102 are considered decoupled from one another. To move the grippingcomponents 2140, 2142 into a non-neutral or compressed position, aholder or instrument is inserted into the recesses 2147, 2149 in theplate. The instrument is designed to press against the angled backsurfaces of the gripping components 2140, 2142, which causes then toangle and compress the spacer 2102.

FIGS. 147A-147C illustrate the spacer and plate assembly with thegripping features of the plate in a compressed position in accordancewith some embodiments. In this non-neutral configuration, the plate 2104and spacer 2102 are considered temporarily coupled to one another. Tomove the gripping components 2140, 2142 back to its neutral position, aholder or instrument simply needs to be retracted. A built in springforce will bring the gripping components 2140, 2142 back to the neutralposition.

FIG. 148 is a top perspective view of a spacer and plate assemblyaccording to a twenty-first embodiment. The spacer and plate assembly2200 comprises a spacer 2202 and a plate 2204. The spacer 2202 and plate2204 are configured to be delivered to a surgical site, for example, viaan insertion tool 2206 (shown in FIG. 153). In the present embodiment,the insertion tool 2206 comprises a holder 2270 (shown in FIGS. 153-160)that holds both the spacer 2202 and the plate 2204 thereon. Oncedelivered, the insertion tool can be removed, thereby leaving the spacer2202 and the plate 2204 in place. At the surgical site, the spacer 2202and plate 2204 may be left decoupled and unfixed to one another.

The spacer 2202 comprises a body 2208 extending along a centrallongitudinal axis 2209 and having a superior surface 2210 and aninferior surface 2212, each having one or more fixation elements 2214 inthe form of protrusions, pyramids, teeth, ribbing, or other texture. Theone or more fixation elements 2214 serve to grip bone in an adjacentvertebral body. The body 2208 of the spacer 2202 comprises an anteriorportion 2220 and a posterior portion 2222 separated by first and secondlateral sides 2216, 2218. The first lateral side 2216 extends along afirst side of the longitudinal axis 2209, while the second lateral side2218 extends along an opposing side of the longitudinal axis 2209.

In some embodiments, the body 2208 comprises a “C” shape, wherein thelateral sides 2216, 2218 form curved arms that surround an inner space2223 for receiving graft material therein. The inner space 2223 issurrounded by an inner wall or surface 2227 that curves along aninterior of the spacer 2202.

In some embodiments, the spacer 2202 comprises one or more chamfers 2229that allow for clearance of bone fasteners or screws that are insertedthrough the plate 2204. In some embodiments, the spacer 2202 comprises apair of chamfers 2229, one found on each of the lateral sides 2216, 2218of the spacer 2002.

The inner surface 2227 along lateral side 2216 includes a prong receiver2241 that is sized to receive a prong 2294 of the holder 2270 (shown inFIG. 156). The prong receiver 2241 is open to the inner space 2223 ofthe body 2208 of the spacer 2202.

As shown in FIGS. 148-150, a rod receiver 2226 is formed in theposterior portion 2222 along the lateral side 2218 and extends along anoblique axis 2227 relative to the longitudinal axis 2209. In someembodiments, the rod receiver 2226 is a female threaded bore. Inalternative embodiments, the rod receiver 2226 can be a smooth bore,with a separate threaded insert (not shown) inserted into the bore 2226.

The female threaded rod receiver 2226 is configured to receive a malethreaded distal end 2274 of a threaded rod 2272 of the holder 2270.While a male and female threaded connection is shown, those skilled inthe art will recognize that the male and female connection may bereversed or other types of connections, such as, for example, a quarterturn key-style lock, can be used to secure the rod 2272 to the spacer2202.

In some embodiments, the threaded rod receiver 2226 extends from theposterior portion 2222 only partially through the lateral side 2218 ofthe spacer 2202 (e.g., a blind hole). While in other embodiments (notshown), the threaded rod receiver 2226 can extend completely through theanterior portion 2020 of the spacer 2002, and in other embodiments, thethreaded bore 2026 extends completely through the lateral side 2218 ofthe spacer 2202.

As shown in FIG. 150, the body 2208 of the spacer 2202 includes firstand second recesses or indentations 2217, 2219. Indentation 2217 isformed along the lateral side 2216, while indentation 2219 is formedalong the lateral side 2218. The indentations 2217, 2219 serve toreceive fingers 2238, 2240 of the plate 2204. The indentations 2217,2219 help to stabilize the spacer 2202 and plate 2204 relative to oneanother when they are operatively coupled via the holder 2270. Recesses2260, 2262 in the indentations 2217, 2219, respectively, extendanteriorly from posterior portion 2222 toward the anterior portion 2220.The recesses 2260, 2262 are sized to accept prongs (not shown) on theplate 2204 to stabilize the connection between the spacer 2202 and theplate 2204. The spacer 2202 and plate 2204 can be formed of suitablebiocompatible materials, including synthetic and natural materials. Insome embodiments, the spacer 2202 is formed of bone, PEEK or titanium,and the plate 2204 is formed of titanium.

The plate 2204 comprises a body 2230 having a superior surface 2232 andan inferior surface 2234. Portions of the superior surface 2232 andinferior surface 2234 may include stabilizer elements 2236. In someembodiments, the stabilizer elements may comprise protrusions, pyramids,or ribbing that are designed to provide torsional stabilization.

The plate 2204 further comprises a posterior portion comprisingthrough-holes 2264, 2266, 2268 for receiving fasteners therein. In thepresent embodiment, the plate 2204 further includes locking screws 2271,2273, 2275, each associated with one of the through-holes 2264, 2266,2268. The locking screws 2271, 2273, 2275 each have cut-away regionsthat allow for entry or removal of fasteners through the plate 2204 inone configuration, but prevent backout of the fasteners when rotatedinto a second configuration. In some embodiments, the plate 2204 furthercomprises a pair of non-threaded bores 2244, 2246, each of differentsizes. Non-threaded bore 2244 extends fully through the plate 2204 andis configured to allow the prong 2294 of the holder 2270 to passtherethrough and into the prong receiver 2241 in the spacer 2202 (shownin FIG. 156), while bore 2246 is a rod opening that is configured toreceive the distal end 2274 of the rod 2272 and allow the distal end2274 of the rod 2272 to pass therethrough and into the spacer 2202(shown in FIG. 156). Non-threaded bore 2244 is a prong opening thatborders through-hole 2264. In some embodiments, the non-threaded bores2244, 2246 each comprises a square, while in other embodiments, thenon-threaded bores 2244, 2246 each comprises a square with roundedcorners or edges or, alternatively, can be other shapes, such astriangular, pentagonal, hexagonal, and the like. Both bores 2244, 2246extend along an axis 2227 that is oblique to the longitudinal axis 2209so that the rod 2272 in the holder 2270 can pass through the holder 2270and engage both the plate 2204 and the spacer 2202 without interferingwith or obstructing any graft material inserted into the inner space2223.

The plate 2204 further comprises a pair of arms or fingers 2238, 2240extending from the posterior portion of the plate 2204. The fingers2238, 2240 comprise extensions that are configured to be received in theindentations 2217, 2219 of the spacer 2202 when the holder 2270 holdsthem together. Advantageously, the fingers 2238, 2240 of the plate 2204are configured to abut surfaces of the spacer 2202 without tightlygripping the spacer 2202, thereby allowing the spacer 2202 to bedecoupled from the plate 2204 upon delivery to a surgical site. Byproviding a decoupled plate 2204 and spacer 2202, each canadvantageously be delivered on their own, or together via an insertiontool, such as the holder 2270. The fingers 2238, 2240 provide stabilitywhen the plate 2204 is used without the spacer 2202.

FIG. 149 is a posterior view of the assembly shown in FIG. 148. Fromthis view, one can see the through-holes 2264, 2266, 2268 formed in theplate 2204 for receiving bone fasteners or screws therein. In someembodiments, the through-holes 2264, 2266 are configured to receive bonefasteners in a downward direction, while through-hole 2268 is configuredto receive a bone fastener in an upward direction.

FIG. 153 is a top perspective view of the assembly shown in FIG. 148attached to the insertion tool 2206. The insertion tool 2006 comprisesthe holder 2270 and the rod 2272. The holder 2270 includes a holder body2280 having a proximal end 2282, a distal end 2284 having a plateengaging surface 2286, a mid portion 2290 disposed between the proximalend 2282 and the distal end 2284, and a channel 2292 extending throughthe holder 2270 between the proximal end 2282 and the distal end 2284.

The proximal end 2282 of the holder 2270 has a first width and the midportion 2290 of the holder 2270 has a second width, less than the firstwidth such that the mid portion 2290 extends wholly on one side of thelongitudinal axis 2209, as shown in FIG. 154. The size and location ofthe mid portion 2290 allows a user to grip the holder 2270 andmanipulate the holder 2270 during insertion of the assembly 2200.

The channel 2292 has an arcuate, or curved, shape within the distal end2284 in order for the rod 2272 to be able to curve within the channel2292 and pass through the rod opening 2246 in the plate 2204. Tofacilitate formation of the curved portion of the channel 2292, in anexemplary embodiment, the holder 2270 is constructed from an upperportion 2296 and a lower portion 2298 (shown in FIG. 155), with thelower portion 2298 being bonded to the upper portion 2296 along abonding line 2299. The curvature of the channel 2292 has a sufficientlylarge radius such that the amount of deflection of the rod 2272 isminimized, reducing frictional engagement of the rod 2272 within thechannel 2292 as the rod 2272 is inserted through the channel 2292.

A prong 2294 extends distally from the distal end 2284. The prong 2294is sized to extend through the prong opening 2244 and into the prongreceiver 2241 to stabilize the assembly 2200 on the insertion tool 2206during insertion. A rod opening 2295 is formed at the distal end 2284and extends along an oblique angle relative to the longitudinal axis2209 so that the rod opening aligns with the rod opening 2246 in theplate 2204, allowing the rod 2272 to be inserted through the channel2292 and the rod opening 2246, and into the rod receiver 2226.

The rod distal end 2274 is sized to be inserted into the proximal end2282 of the holder 2270, through the channel 2292 in the holder body2270, through the rod opening 2246 in the plate 2204 and into the spacer2202 such that the distal end 2274 releasably engages the rod receiver2226. The rod 2272 may be constructed from an elastic metal such as, forexample, Nitinol, which allows the rod 2272 to bend as the rod 2272 isadvanced through the channel 2292.

Optionally, although not shown, the holder 2270 can also includechannels for anchors, as well as openings for screws to pass through forsecuring the plate 2204 to vertebrae (not shown).

The holder 2270 advantageously operatively couples the spacer 2202 andplate 2204 during delivery to a surgical site. The engaging surface 2286of the distal end 2284 of the holder 2270 abuts the plate 2204 so thatthe assembly 2200 is securely connected to the insertion tool 2206.

FIG. 154 is a top view of the assembly 2200 shown in FIG. 148 attachedto the insertion tool 2206. From this view, one can see how the midportion 2290 of the holder 2270 is offset from the longitudinal axis2209 of the assembly 2200.

FIG. 155 is a side view of the assembly 2200 shown in FIG. 148 attachedto the insertion tool 2206. From this view, one can see how the spacer2202 and plate 2204 are inserted into a surgical site. The spacer 2202comprises a tapered leading end that aids in insertion of the assembly2200.

FIGS. 157-160 illustrate the insertion tool 2206 being attached to thespacer and plate assembly 2200 in accordance with some embodiments. FIG.157 illustrates the holder 2270 prior to insertion of the rod 2272 intothe channel 2292. FIG. 158 illustrates the insertion tool 2006 fullyassembled with the rod 22732 having been inserted into the holder 2270.FIG. 159 illustrates the insertion tool 2206 engaged with the plate2204, but not yet engaged with the spacer 2202. FIG. 160 illustrates thespacer 2202 engaged with the holder 2270, with the threaded distal end2274 of the rod 2272 engaging the threaded bore 2226 of the spacer 2202,thereby operatively coupling the spacer 2202 and plate 2204 duringdelivery to a disc space.

Once delivered, the insertion tool 2206 can then be removed from theassembly 2200 by unthreading the rod 2272 from the spacer 2202 andremoving the insertion tool 2206. Next, bone fasteners can be insertedinto the plate 2204 to thereby fix the plate 2204 to one or moreadjacent vertebrae. The plate 2004 and spacer 2002 may be left in thesurgical site, uncoupled to one another.

All of spacers 102-2202 described above can be constructed frombiocompatible material, such as, for example, bone, PEEK, titanium, withor without surface treatments, and with varying porosity.

In some embodiments, any of the plates and spacers described above canbe accompanied by other surgical implants, including rods and screws.One of skill in the art will appreciate that any of the plates andspacers can be used on multiple levels of the spine.

It will be further understood that various changes in the details,materials, and arrangements of the parts which have been described andillustrated in order to explain the nature of this invention may be madeby those skilled in the art without departing from the scope of theinvention as expressed in the following claims.

What is claimed is:
 1. A spacer assembly having a central longitudinalaxis, the assembly comprising: a spacer having a generally “C” shapedbody having a first lateral side, a second lateral side, and an innerspace defined between the first lateral side and the second lateralside, the first lateral side having an unthreaded prong receiver open tothe inner space and the second lateral side having a threaded rodreceiver, the rod receiver extending along an axis oblique to thecentral longitudinal axis; and a plate releasably attached to thespacer, the plate having a first finger adapted to releasably engage thefirst lateral side and a second finger adapted to releasably engage thesecond lateral side, a prong opening extending therethrough, the prongopening being adapted to align with the prong receiver, and a rodopening extending therethrough, the rod opening extending along the axisoblique to the central longitudinal axis and being adapted to align withthe rod receiver.
 2. The spacer assembly according to claim 1, whereinthe rod receiver comprises a blind threaded hole.
 3. The spacer assemblyaccording to claim 1, wherein the first lateral side comprises a firstindentation and wherein the second lateral side comprises a secondindentation, wherein the first finger is releasably insertable into thefirst indentation and the second finger is releasably insertable intothe second indentation.
 4. The spacer assembly according to claim 1,wherein the rod opening in the plate is unthreaded.
 5. The spacerassembly according to claim 1, wherein the inner space is surrounded byan inner wall that curves along an interior of the spacer.
 6. The spacerassembly according to claim 1, wherein bone fasteners are insertedthrough the plate.
 7. The spacer assembly according to claim 6, whereinthe spacer comprises one or more chamfers configured to allow forclearance of the bone fasteners.
 8. The spacer assembly according toclaim 1, wherein the plate includes a superior surface and an inferiorsurface, and portions of the superior surface and/or the inferiorsurface include stabilizer elements configured to provide torsionalstabilization.
 9. The spacer assembly according to claim 1, wherein theprong receiver and the prong opening are sized to accept a prong of aninsertion tool and wherein the rod receiver and the rod opening aresized to accept a rod of the insertion tool.
 10. The spacer assemblyaccording to claim 1, wherein once at a surgical site, the spacer andthe plate are decoupled and unfixed to one another.
 11. A spacerassembly having a central longitudinal axis, the assembly comprising: aspacer having a generally “C” shaped body having a first lateral side, asecond lateral side, and an inner space defined between the firstlateral side and the second lateral side, the second lateral side havinga threaded rod receiver, the rod receiver extending along an axisoblique to the central longitudinal axis; and a plate releasablyattached to the spacer, the plate having a first finger adapted toreleasably engage the first lateral side and a second finger adapted toreleasably engage the second lateral side, a rod opening extendingthrough the plate, the rod opening extending along the axis oblique tothe central longitudinal axis and being adapted to align with the rodreceiver.
 12. The spacer assembly according to claim 11, wherein the rodreceiver comprises a blind threaded hole.
 13. The spacer assemblyaccording to claim 11, wherein the first lateral side comprises a firstindentation and wherein the second lateral side comprises a secondindentation, wherein the first finger is releasably insertable into thefirst indentation and the second finger is releasably insertable intothe second indentation.
 14. The spacer assembly according to claim 11,wherein the rod opening in the plate is unthreaded.
 15. The spacerassembly according to claim 11, wherein the inner space is surrounded byan inner wall that curves along an interior of the spacer.
 16. Thespacer assembly according to claim 11, wherein bone fasteners areinserted through the plate.
 17. The spacer assembly according to claim16, wherein the spacer comprises one or more chamfers configured toallow for clearance of the bone fasteners.
 18. The spacer assemblyaccording to claim 11, wherein the plate includes a superior surface andan inferior surface, and portions of the superior surface and/or theinferior surface include stabilizer elements configured to providetorsional stabilization.
 19. The spacer assembly according to claim 11,wherein the rod receiver and the rod opening are sized to accept a rodof an insertion tool.
 20. The spacer assembly according to claim 11,wherein once at a surgical site, the spacer and the plate are decoupledand unfixed to one another.